J/MNRAS/434/1411 Variability of broad emission lines in QSOs (Woo+, 2013)
Variability of broad emission lines in high-luminosity, high-redshift quasars.
Woo S.C., Turnshek D.A., Badenes C., Bickerton S.
<Mon. Not. R. Astron. Soc., 434, 1411-1421 (2013)>
=2013MNRAS.434.1411W 2013MNRAS.434.1411W (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Spectroscopy
Keywords: galaxies: active - galaxies: nuclei - quasars: general -
galaxies: Seyfert
Abstract:
We examine the variability of the high-ionization Lyα
λ1216 broad emission line (BEL) in a sample of 61
high-luminosity, high-redshift quasars observed at two epochs by the
Sloan Digital Sky Survey. These bright objects lie in the redshift
interval z=[2.5, 4.3] and have luminosities
3.4x1045≲λ*Lλ≲3.4x1046erg/s at 1450Å.
Utilizing improved spectrophotometric flux calibrations relative to
nearby compact stars observed simultaneously, we are able to measure
the flux changes in Lyα and the nearby continuum at two epochs.
We find 20 objects that exhibit Lyα BEL flux variability at a
significance level greater than 5σ on time-scales ranging from
days to years in the quasar rest frame.
Description:
For this study, we used the SDSS data release (DR8, Aihara et al.
(2011ApJS..193...29A 2011ApJS..193...29A)) to select an appropriate sample of quasars. In
the observed frame, SDSS spectra cover the optical to near-infrared
(3800-9200Å) with resolution λ/Δλ∼2000 at
5000Å (Stoughton et al., 2002AJ....123..485S 2002AJ....123..485S). To define our quasar
sample and ensure that Lyα λ1216 BELs are included in the
spectra, we selected objects which are spectroscopically classified as
QSOs, have redshifts in the interval z=[2.5-5.0] and have multiple
spectroscopic observations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 185 61 BEL and continuum flux measurements for sixty-one
quasars after recalibration using surrounding
compact objects
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See also:
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS SDSS name (HHMMSS.ss+DDMMSS.s)
20- 24 I5 d HMJD Epoch of HSN flux measurement (MJD)
26- 30 I5 d LMJD Epoch of LSN flux measurement (MJD)
32- 37 F6.4 --- zem Emission redshift
39- 46 F8.4 d dtau Rest-frame time interval between the
two observation epochs
48- 54 F7.4 mag rmag SDSS r magnitude
56- 63 E8.3 mW/m2 lL1450 Galactic extinction-corrected luminosity
at rest-frame 1450Å (lambda*Llambda)
65- 72 F8.4 10-19W/m2/nm FLyaH HSN-epoch flux at Lymanα BEL (1)
74- 79 F6.4 10-19W/m2/nm e_FLyaH rms uncertainty on FLyaH (1)
81- 87 F7.4 10-19W/m2/nm Fc1300H HSN-epoch flux continuum at 1300Å (1)
89- 94 F6.4 10-19W/m2/nm e_Fc1300H rms uncertainty on Fc1300H (1)
96-102 F7.4 10-19W/m2/nm FCIVH HSN-epoch flux at CIV BEL (1)
104-109 F6.4 10-19W/m2/nm e_FCIVH rms uncertainty on FCIVH(1)
111-117 F7.4 10-19W/m2/nm Fc1600H HSN-epoch flux continuum at 1600Å (1)
119-124 F6.4 10-19W/m2/nm e_Fc1600H rms uncertainty on Fc1600H (1)
126-133 F8.4 10-19W/m2/nm FLyaL LSN-epoch flux at Lymanα BEL (1)
135-140 F6.4 10-19W/m2/nm e_FLyaL rms uncertainty on FLyaL (1)
142-148 F7.4 10-19W/m2/nm Fc1300L LSN-epoch flux continuum at 1300Å (1)
150-155 F6.4 10-19W/m2/nm e_Fc1300L rms uncertainty on Fc1300L (1)
157-163 F7.4 10-19W/m2/nm FCIVL LSN-epoch flux at CIV BEL (1)
165-170 F6.4 10-19W/m2/nm e_FCIVL rms uncertainty on FCIVL (1)
172-178 F7.4 10-19W/m2/nm Fc1600L LSN-epoch flux continuum at 1600Å (1)
180-185 F6.4 10-19W/m2/nm e_Fc1600L rms uncertainty on Fc1600L (1)
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Note (1): BEL stands fro broad emission line.
Fluxes are in 10-17erg/cm2/s/Å unit.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 01-Aug-2014